A common conventional child's water bottle shown in FIG. 4 generally has a very strong band for hanging a bottle body on a shoulder or a neck of a user. And the band is firmly combined with the bottle body, impossible to be separated from the bottle body. So if a child uses it, hanging on his shoulder, there may happen an accident that the band may wind around his neck forcibly by playing fun of the bottle body by another child. And chances are that the band may be hooked by a branch of a tree, if the user goes by the tree.